Fabrication and Characterization of Iridium Oxide pH Microelectrodes Based on Sputter Deposition Method
Ye Xi1, Zhejun Guo1, Longchun Wang1
1National Key Laboratory of Science and Technology on Micro/Nano Fabrication Laboratory, Collaborative Innovation Center of IFSA, Department of Micro/Nano-Electronics, Shanghai Jiao Tong University, Shanghai 200240, China.
Abstract:
pH value plays an important role in many fields such as chemistry and biology; therefore, rapid and accurate pH measurement is very important. Because of its advantages in preparation, wide test range, rapid response, and good biocompatibility, iridium oxide material has received more and more attention. In this paper, we present a method for preparing iridium oxide pH microelectrodes based on the sputter deposition method. The sputtering parameters of iridium oxide are also studied and optimized. Open-circuit potential tests show that microelectrodes exhibit near-Nernstian pH response with good linearity (about 60 mV/pH), fast response, high stability (a slight periodic fluctuation of potential change <2.5 mV in 24 h), and good reversibility in the pH range of 1.00-13.00.
